Optimum Utilization of Electric Circuit Capacity by Adding Electric Vehicle Charging

Abstract

This invention enables Electric Vehicle (EV) charging requirements to be supplied by electric power available off-peak without increasing demand charges. It does this by continually measuring primary loads and enabling EV charging to utilize only that power that will not increase total demand. Grouping software available from Electric Vehicle Service Equipment (EVSE) suppliers allows the available power to be shared among multiple vehicles.

I claim: 
     
         1 . A system comprising;
 Communication equipment and specialized control software to control operation of a group of Electric Vehicle Service Equipments (EVSEs),   A group of Electric Vehicle Service Equipments (EVSEs), which provide electric energy recharging facilities to one or more Electric Vehicles,   A source of electric energy supplying a building or other facility,   A current tap to provide electric energy to the group of EVSEs from the source of electric energy,   An electric energy meter to measure the electric power load on the source in kW, and   Software to enable recharging of the electric vehicle(s) without increasing the measured demand on the source of electric energy,   
     
     
         2 . The system of  claim 1  in which an additional electric energy meter is installed to measure the electric power load on the building, exclusive of the power consumed by the EVSEs. 
     
     
         3 . The system of  claim 1  in which the communication is via a WiFi internet router. 
     
     
         4 . The system of  claim 1  in which the communication is via a cellular phone connection. 
     
     
         5 . The system of  claim 1  in which the software is resident in an on site microcontroller. 
     
     
         6 . The system of  claim 1  in which the software is resident in the cloud. 
     
     
         7 . A method comprising; Installing and operating the system of  claim 1  in which a current tap is installed so as to provide electric energy from a source of electric energy to a remotely controlled group of EVSEs,
 the EVSEs are controlled remotely as a group and their power level can be limited to an amount of available limiting power, designated A, 
 the value of A is transmitted to the group periodically to enable the EVSEs to equally recharge whatever electric vehicles are plugged in at a maximum rate that will not increase electric energy demand on the source of electric energy measured as M, by an electric energy meter, 
 The total system load is limited to the maximum monthly billable demand of the primary load, designated L, by maintaining A<(L-M), and 
 L is updated each monthly billing cycle by recording M at suitable intervals and changing L to the maximum M measured during the month. 
 
     
     
         8 . A method comprising; installing and operating the system of  claim 1  in which an electric energy meter is installed to measure only the primary load on the source of electric energy, designated M,
 The current tap is installed so as to provide electric energy from the source of electric energy to a group of EVSEs, which energy is not measured by the current transformer, 
 the EVSEs are controlled remotely as a group and their power level can be limited to an amount of available limiting power, designated A, 
 the value of A is transmitted to the group periodically to enable the EVSEs to equally recharge whatever electric vehicles are plugged in at a maximum rate that will not increase electric energy demand on the source of electric energy, 
 The total system load is limited to the maximum monthly billable demand of the primary load, designated L, by maintaining A<(L-M), and 
 L is updated each monthly billing cycle by recording M at suitable intervals and changing L to the maximum M measured during the month.